基于改进锁频锁相的高动态同步算法  

High dynamic synchronization algorithm based on modified frequency-locked and phase-locked

作　　者：高玉龙[1,2] 王骐[2] 白旭[1] 沙学军[1] 

机构地区：[1]哈尔滨工业大学通信技术研究所,哈尔滨150080 [2]哈尔滨工业大学光电子技术研究所,哈尔滨150080

出　　处：《计算机工程与应用》2009年第21期25-28,共4页Computer Engineering and Applications

基　　金：国家重点基础研究发展规划(973)(No.2007CB310601);哈尔滨工业大学博士后基金资助~~

摘　　要：针对卫星定位导航系统多谱勒频移大的特点,根据设计的实际系统推导出锁频锁相算法的理论表达式。对叉积算法得到的结果利用改进的平滑算法进行处理,降低了噪声方差。与此同时使锁频环和锁相环同时工作,加快了更新时间。对上述改进算法进行单片FPGA实现,采用NiosII代替传统的DSP对算法的锁频锁相部分进行实现,增加了系统的稳定性和可靠性。通过实验验证,提出的改进算法解决了环路跟踪精度和动态性能不能兼顾的矛盾,各项技术指标达到或超过系统设计的要求。Aiming at the characteristics of navigation satellite system,theoretical expressions of frequency-locked and phase- locked algorithm are gained according to practical system.The results of AFC algorithm are processed using modified smoothed algorithm,and its covariance is decreased.Simultaneously,Frequency-locked loop and costas loop work synchronously,which shorten the update time of them.Above algorithm is realized using single FPGA,frequency-locked loop and phase-locked loop are implemented by NiosII replacing conventional DSP,and these enhance stability and reliability of system.Some tests prove that contradiction between tracking precision and dynamic performance is resolved basically.All required technical guideline of the system are achieved or exceeded.

关 键 词：锁频环 锁相环 高动态同步 NIOSII软核处理器 

分 类 号：TN914.43[电子电信—通信与信息系统]